is he buried under a shed in detroit? the latest attempt to end the 37-year-old mystery of jimmy hoffa. >>> and later, girls cheering on other girls and making a difference. >>> it is one of the most famous and enduring american mysteries, what happened to jimmy hoffa, the teamster's boss who went missing without a trace in 1975. well, now investigators are back on the case just outside detroit. and nbc's john yang is there. >> reporter: could these six-foot cylinders with dark, muddy soil, two inches in diameter, hold the mystery of jimmy hoffa? this man said he saw the body buried years ago, and where ground-penetrating radar showed something, two feet deep. >> we're just doing our job, we had credible information and had to follow through with it. >> reporter: police said when he disappeared in 1975, there was a different shed, the floor was dirt, not yet covered with concrete. it is about 20 miles from where hoffa was last seen, apparently lured by two mob figures, since then, he has been famous, and his organized cri